1. Field
Provided are secondary batteries, and in particular, flexible secondary batteries.
2. Description of the Related Art
Development of electronic technology has led to a rapid expansion of markets for various electronic devices, such as smartphones, smart pads, electronic books, watch-shaped telephones, and mobile medical devices that are attached to the human body, in addition to mobile phones, game players, portable multimedia players (“PMPs”), and moving picture experts group (“MPEG”) audio layer-3 (“MP3”) players.
Due to the growth of the markets for such mobile electronic devices, a demand for batteries that are suitable for driving these mobile electronic devices is increasing. In addition, a demand for flexibility of the mobile electronic devices is increasing in relation to the use, movement and safekeeping of the mobile electronic devices and to the durability against a shock. Consequently, a demand for flexibility of a battery is also gradually increasing to embody the flexibility of these mobile electronic devices.